Development of Piezoresistive Bar Gage

Abstract

Abstract : This report describes the adaptation of pressure bar techniques for pressure measurement to the development of a more reliable, useable, and rugged pressure gage for measuring pressure (up to 10,000 psi) in blast chambers and shock tubes. The pressure bar gage, used for years as a piezoelectric transducer, was converted to a piezoresistive transducer for easier use in field tests. Preliminary evaluation tests in the laboratory indicate that this gage combines the good dynamic response of damped pressure bar gages (fast rise time with little overshoot and ringing) with the static response capabilities and reliability of the more common diaphragm pressure gages. Initial use in a field test indicated that the gage can survive high-velocity debris impact, although usually with some zero offset. This offset can probably be eliminated by using soft debris shields.